@Rockhead,
Heh, a little off the subject rocky, but that reminded me of something from years ago.
My BF and I were living together, and usually had a roommate to help pay expenses.
This one guy didn't last the month.
He was young, which wasn't a problem, so were we.
But he moved in directly from Mommy and Daddy's house, and to him this was going to be a great adventure, staying up as late as he wanted, having friends over any time, etc.
For the first week, I didn't say anything when I'd walk in the kitchen, and find his empty plate and glass in the sink. I'd just wash it along with whatever I came in to wash of my own.
After that, I decided just to leave it. After 2 weeks he said "There aren't any clean forks (or whatever)" I swear to God it sounded like he was going to say "Mom" before that.
Obviously I said "That's because you've used them all up. You haven't noticed that no one is cleaning your dishes, and the pile just gets bigger and bigger?"
He looked confused, seriously. I could tell he just swear to God never thought about stuff like dishes got cleaned and put away.
So, you could put a bucket of dog poop in front of some people doors, and they really won't get the connection that it's the **** that came out of their own dogs ass.